Bought a Koala earlier this year and here's my suggestions to anyone thinking about purchasing one. Test drive it first! Had I known then what I know now I wouldn't have gotten the Quiltmate IV I would have gotten the Sewingmate and I would have gotten a taller one.
With the Quiltmate your machine is in the center of the table. Nice having drawers on both sides but if you're quilting a larger quilt you'll not be using the other 1/3 of the table on the right of your machine. With the Sewmate you'll have the entire table to use.
I'm only 5 ft 4 1/2 and wish I had gone with the 33 inch high table. I would have gone with the taller so I don't have to lean over as much. Other than that I love love love my Koala!!
Hugs